Crystal structures of artificial metalloproteins: tight binding of FeIII(Schiff-Base) by mutation of Ala71 to Gly in apo-myoglobin.

Abstract

Apo-myoglobin (apo-Mb) and apo-A71GMb were successfully reconstituted with FeIII(salophen) (1) (salophen = N,N'-bis(salicylidene)-1,2-phenilenediamine), Fe(III)(3,3'-Me2-salophen) (2), and FeIII(5,5'-t-Bu2-salophen) (3). The crystal structure of 2.apo-A71GMb shows the tight binding of the complex in the Mb cavity, while in wild-type apo-Mb it is highly disordered due to the steric repulsion with Ala71. Furthermore, the structure of 2.apo-A71GMb suggests a possible accommodation of a small substrate in the cavity. In fact, the cyanide association rate constant of 2.apo-A71GMb is 216-fold larger compared to that of 2.apo-Mb. These results provide us principles for the noncovalent fixation of synthetic metal cofactors at the desired positions in protein matrixes.

Cite this paper

@article{Ueno2004CrystalSO, title={Crystal structures of artificial metalloproteins: tight binding of FeIII(Schiff-Base) by mutation of Ala71 to Gly in apo-myoglobin.}, author={Takafumi Ueno and Masataka Ohashi and Masaharu Kono and Kazuyoshi Kondo and Atsuo Suzuki and Takashi Yamane and Yoshihito Watanabe}, journal={Inorganic chemistry}, year={2004}, volume={43 9}, pages={2852-8} }